of philadelphia



UNITED STATES PATENT OFFICE.

' HENRY WIEDERHOLD, OF PHILADELPHIA,- PENNSYLVANIA, QASSIGNOR TO THE BARBER ASPHALT PAVING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION or WEST VIRGINIA.

BITUMINOUS LINING FOR SURFACES EXPOSED T0 CORROSIVE ACTION.

1,305,678. No Drawing.

To all whom it may conccm:

Be it known that I, HENRY Wmnnnnonn, of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have in vented certain new and useful Improvements in Bituminous Linings for Surfaces Exposed to Corrosive Action, whereof the following is a specification.

My invention relates to a bituminous composition for use in lining tanks and other surfaces whichare exposed to the corrosive action of acid or alkaline fumes or liquids.

Attempts have heretofore been made to prepare a mastic for the lining of surfaces exposed to corrosive action. Especially has this attempt been made in the lining of acid tanks used in various industries; but experience has shown that the mastics thus, produced have not been able to withstand the action of the acid, but have disintegrated as a result of such action. Such mastics have usually been made from the calcareous rock asphalts which consist essentially of about ninety per cent. lime-stone, and ten per cent. bitumen or maltha, and occur extensivel as such in nature. Somewhat similar arti cial mixtures of asphaltum and pulverized limestone have been prepared and used for the same purpose.

I have discovered that the cause of the failure of these mastics is that the particles of calcareous rock which such natural or artificially prepared compositions of asphaltum or bitumen have contained are disintegrated when exposed to acid or alkaline solutions or corrosive gases even though the mineral aggregate of such compositions is completely embedded within and therefore covered by a bitumen which in itself is not affected by such agents. I

In order to overcome this difliculty, I have prepared a bituminous com sition which is especially useful and value. 1e for the purpose of lining large tanks constructed from hydraulic concrete for use in metallurgical processes and other industries in which mineral acids are employed. This composition is prepared by employin asphaltum such as Trinidad asphalt or ermfidez asphalt or gilsonite or similar asphalts, free from calcareous material, or even that pro-' duced by the manipulation of oils with an fasphaltic base, and combining such asphalt or a mixture of such asphalts, in a melted or Specification of Letters Patent.

' Patented June 3, 1919.

Application filed January 2, 1915. Serial No.

fluid condition, with a graded mineral aggregate of rock such as quartz, granite, trap or otherigneous rock,'which is entirely free from carbonates. I find that a suitable pr0- portion in which to combine these materials is asphaltum from 15 to 35 parts, finely powdered igneous rock, sand or clay not any coarser than one tenth of an inch, from 25 to 50 parts, and coarser mineral particles of igneous rock, sand or clay between one-tenth aggregate and stirring the mass until each particle of the mineral aggregate is coated with the asphaltum, and the composition is n such condition that it may be spread out pen or cast against the surface of the supporting structure, whether concrete, wood or metal. Such composition is plastic and may be spread as mastic or cast into forms at temperatures in excess of 250 F. When set it will retain its form and place at temperatures below 125 F. In view of. the fact that all rock does not crush with the same fracture, or to the same grading as to size, it is obvious that the roportion of fine and coarse articles in t e mineral aggregate and also 0 the asphaltum must necessarily be varied to some extent and within reasonable limitations in order to produce a composiw tion having the Working properties desired.

For practical purposes the mineral matter ments upon which the corrosive fumes or calcareous material, with a mineral aggresmaller than one-tenth of an inch, about 25 gate consisting of particles graded in size to 50 parts, and coarse mineral particles of from grit to dust, said particles being subigneous rock, larger than one-tenth of an 5 stantia-lly free from carbonates, which are inch, about 30 to 45 parts. 5 mechanically. acted upon by said corrosive In testimony whereof, I have hereunto fumes or liquids. signed my name at Philadelphia, Pennsyl- 2. A bituminous composition for use as a 'vania, this thirtieth day of December, 1914.

protective coating for surfaces exposed to HENRY -WIEDERHOLD the action of corrosive fumes or liquids,

10 containing in combination about 15 to 35 Witnesses:

parts of asphaltum free from calcareous ma- J AMES H. BELL, terlal, fine non-calcareous mineral particles E. L. FULLERTON. 

